题目：Development of super-resolution microscopy and its application in subcellular imaging

报告人：陈轩泽（北京大学）

主持人：李向平研究员

时间：2016年12月23日下午2:30

地点：曾宪梓科学馆405会议室

报告摘要：

In the past centuries, optical microscopy has been demonstrated to be one of the most powerful biophysical tools inlife sciences. Particularly, ﬂuorescence microscopy allowsresearchers to study specific ﬂuorescence-labeled structuresand spatiotemporal dynamics at the cellular and even single-molecule levels. However, the spatial resolution of conventional ﬂuorescence microscopy is limited by the Abbediffraction limit.The last two decades have witnessed revolutionary advancesin far-field super-resolution ﬂuorescence microscopy (nanoscopy), which overcomes the diffraction barrier and offers anunprecedented view of the subcellular world.

Herein, we reported our recent development in fluorescence nanoscopy. Several studies were carried out: (1) A joint-tagging super-resolution optical fluctuation imaging (JT-SOFI) labeled using quantum dots was developed to improve the spatiotemporal resolution and labeling density. (2) Combining with two-photon light-sheet microscopy and spinning disk confocal microscopy, fast 3D whole cell SOFI imaging was achieved. (3) A new high brightness, high on/off contrast, strong photostability reversibly switchable fluorescent proteins, Skylan-S, was developed to achieve high spatiotemporal live-cell SOFI imaging. (4) A new type of ultra-high brightness, extraordinary photostability and superior biocompatibility photoblinking small polymer dots (Pdots), were developed, for the first time, and used in long-term SOFI imaging. We also studied the dynamic process of RNA Pol II clusters in live-cell nucleus using quantitative 3B imaging. For the first time, the dynamic processes of individual Pol II clusters, including both cluster assembly and disassembly are directly observed. We revealed the asynchronous nature of Pol II cluster. Our results support the on-demand model for transcription factory formation.